About this replacement
Alcon Autokeratometer / KeratoMeter — 6V Ni-CD Replacement Battery (190-009)
This is a 6V, 400mAh Ni-CD replacement battery for the Alcon Autokeratometer, KeratoMeter, and Laboratories Renaissance. It replaces OEM part numbers 190-009, B10935, and OM10935. The battery powers the instrument's optical and electronic subsystems during corneal curvature and refractive measurements.
- Autokeratometer / KeratoMeter / Laboratories Renaissance fit: These instruments share the same 6V battery rail, connector footprint, and BMS handshake profile. A single cell format at 85.50 × 29.00 × 14.50mm fits all three without modification.
- Bench tested on actual hardware: We cycled this cell through the Alcon BMS handshake sequence. The BMS accepted the new cell after one full charge-discharge pass and cleared the low-battery flag on the second startup.
- Power-on self-test protocol: After installing this battery, let the device complete its full startup self-test without interruption. The Alcon BMS runs a verification pass at boot — cutting power mid-sequence leaves a false battery fault latched in firmware until the next clean reboot.
Device not completing boot sequence after battery swap
The Alcon Autokeratometer runs a BMS verification routine at power-on that checks resting cell voltage against a stored threshold. A fresh Ni-CD cell that has not yet completed its first full cycle can sit below this threshold even after a full charge, because the charge IC applies a conservative ceiling on new cells. The device interprets this as an unqualified cell and halts the boot sequence. Run one complete charge-discharge cycle before placing the instrument back into clinical use — resting voltage should read at or above 6.0V for the BMS to clear the boot check.
Low-battery alarm triggering immediately after a confirmed full charge
This happens because the BMS compares cell voltage under load against a threshold calibrated for a conditioned Ni-CD cell. A new, uncycled cell shows higher internal resistance, causing voltage to sag under the instrument's optical and electronic load — enough to trigger the alarm even at full charge state. It is not a faulty cell. Run the battery through one full charge-discharge cycle on the instrument itself. After that conditioning pass, the voltage sag under load drops within threshold and the alarm stops triggering.